Electrical switch.



C. L. TERRY @a P. TWNSBIYD.

ELECTRICAL SWITCH.

APPLIGATION PILEB JAN. 17, 1910.

patented 051.1231911.

UNITED sTA'rEs PATENT Ere.

CARLTON L. TERRY AND PITT TOWNSEND, OF CLEVELAND, OHIO.

ELECTRICAL SWITCH.

Specification of Letters Patent.

' Application filed January 1 To all 'whomfit may comn:

and Prr'r T owxsunn, citizens of the United ments in Electrical Switches,

States, residing at Cleveland, inthe county of Cuyahoga and Stateof Ohio, havein-A vented certain new and useful Improveof which the following is a specification.

This invention relates to electrical switches, and has for its special object to provide a nonsparking switch or connecting device, by means of which branch circuits maybe connected or disconnected without arcing between contacts. rlhis object is effected b vproviding fa structure in which the plugs of the branch lines cannot be inserted or removed vwhile the main circuit is closed, the switch actuatingv device carrying amember which prevents disconnection or connection of the branch circuits when the switch is closed. ,l

Various other advantages of construction will be apparent from the following description and .accoilnpanying drawings. p

In the drawings-li`igure 'l is a central vertical section of the switch receptacle and attaching parts. l? ig. 2 is va plan view thereof, one of the branch plugs being removed from its socket.

Referring specifically to the drawings, 13 indicates an air tight switch box which may be filled with oil if desired. The switch shaft 2 projects into this box through a gland in the top,A and is provided with a handle lever l for operation. The branch circuit cables, are indicated at 3 and 3, and these terminate respectively in plugs 4. and 4, arranged to be 'inserted in sockets 5 and 5 in the casing. The plugs have headsof insulation 20, and the sockets are bushed with insulation 2l. Attached to the respective sockets are opposite brush contacts or members G and G which reccivethe upper knives 7 and 7 connected by rivets 8 to the lower knives ll and ll which Contact with the lower brushes l() and l0 attached to the sockets 9 and 9 for the main cables l2 and l2. The knives are mounted upon blocks of insulation il() secured to the shaft Q, and an insulating plate I6 projects from the shaft between the upper and lower brushes for the purpose of preventing areing between the main and branch terminals. rThe circuit is opened and closed by turning the shaft 2 to connect or disconnect the plates from the brushes.

shape to engage o ver Patented oer. i7, i911;

7, 1910. Serial yNo. 538,517. v

14C is a removable lid for the switchv box.

The outer end of the shaft 2 has mounted thereon a locking member l5 consisting of bent arms of insulating material projecting oppositely from the shaft, the insulation being strengthened bymetallic segments l5. These locking arms are of proper size and the. anges 20 of the heads on the plugs when said plugs are in place, as shown in full lines-in Figs. l and 2, and the'arrangement is such thaty when in this position the switch is closed. The locking engagement of said arms over said plugs prevents the removal of the plugs until the switch is turned to open position, as shown in dotted lines in Fig. 2. Furthermore the plugs cannotswitch is turned to open position. Accordingly arcing incident to the insertion or removal of the plugs when the switch is closed is prevented, and hence the device may be safely used in mines and other places where danger of ignition of gas exists.

What we claim as new is l. The combination of al having sockets therein, connecting plugs adapted to fit into said sockets, a switch lever adapted to open and close the' switch, and swinging arms operatively connected to said leverand engageable with said plugs to prevent insertion or removal of the plugs when the switch is closed.

2. rThe combination of a switch box having sockets therein opening through the wall of the box, connecting plugs adapted to fit into said sockets,'a switch shaft extending through the wall of the box and provided with a handle, and a` locking member carried by said shaft, outside of the casing, and engaging the plugs to lock the same in the sockets when the switch is closed.

3. The combination of a switch box having sockets therein, a switch lever, connecting plugs fitting into said sockets and having heads, and `a swinging locking member operatively connected 'to the lever and turning therewith and engageable with the heads to lock the plugs in the sockets when the switch is closed.

4. The combination of a switch box having sockets for attaching plugs opening through the wall thereof, a `switch lever including a shaft. extending into the box bearranged to swing over the sockets, when the switch t ca sing be inserted until the switch is closed, to prevent insertion or removal of the plugs.

5. The combination of a switch box having terminals therein, connecting plugs adapted to engage said. terminals, a switch shaft extending through the wall of the box and provided with a handle, and a locking member carried by said shaft, outside of the casing, and engaging the plugs to lock the same in engagement with the terminals when th'e switch is closed. 6. The combination of a switch boX having terminals therein, a switch shaft, connecting plugs engaging said terminals and having heads, and a swinging locking member carried by the shaft and turning therewith and engageable with the heads to lock the plugs in engagement with the terminals when the switch is closed.

7. In a device of the class described, the combination of a fiame proof casing, switch contacts within the casing, a shaft within the casing and operable from a point outside,

a switch arm mounted on the shaft and y adapted to engage the switch contacts to connect them, a terminal connected to one of the switch contacts, a conductor plug adapted to engage the terminal, and a locking arm connected to the shaft and adapted to engage the plug to lock it in engagement with the terminal when the switch arm is in engagement with the contacts.

8. In a device-of the class described, the combination of a ame proof switch, a shaft for operating the switch, a terminal connected to the switch, a conductor plug adapted to engage the terminal, an arm connected to the shaft and provided with a fork having prongs adapted to engage the plug to hold it in engagement with the terminal when the switch. is in closed position.

9. In a device of the class, described, the combination of a casing, a switch in the casing, a switch operating device, conductor terminals within the casing connected with the switch, connecting plugs adapted to engage the terminals and a movable device outside of the casing for holding the plugs in or out of engagement with the terminals, and a means operably connecting the said holding device with the switch operating device, whereby the holding device is maintained in operative position when the switch is closed.

10. The combination of a 'itch box having a terminal therein, a connecting plug adapted to engage said terminal, a switch shaft extending through the wall of the Ybox and provided with a handle, and a locking member carried by said shaft, outside et the casing, and engaging the plug to lock the same 1n engagement with the terminal when the switch is closed.

ll. The combination of a switch box having a terminal therein, a switch lever, a connecting plug engaging said terminal and having a head, and a swinging locking member operatively connected to the lever and turning concentrically therewith and engageable with the head to lock the plug in engagement with the terminal when the switch is closed.

In testimony whereof, we do atiX our signatures in presence of two witnesses.

CARLTON L. TERRY. PITT TOWNSEND.

Witnesses:

HARRY A.. THOMPSON, C. V. LLOYD. 

